1. Field of the Invention
The present invention relates to a semiconductor light emitting device manufactured by growing semiconductor layers on a GaAs substrate and a method for manufacturing the same.
2. Description of the Related Art
A semiconductor light emitting device in which semiconductor layers including a light emitting layer composed of an InGaAlP layer or the like are stacked on a GaAs substrate is hitherto known. However, the conventional light emitting device has a problem that the output light emitted to the outside is small because the GaAs substrate absorbs light emitted by the light emitting layer. To solve the problem, there is a known technique of removing the substrate by abrasion. However, removing the substrate by abrasion causes another problem of cracks occurring in the semiconductor light emitting device cracks. Therefore, there is a disclosure of a technique to solve such a problem of cracks of the semiconductor light emitting device occurring at removal of the substrate.
For example, Japanese Patent Laid-open Publication No. 1999-168236 (Patent Literature 1) discloses a semiconductor light emitting device manufactured by growing semiconductor layers including a light emitting layer composed of an InGaAlP layer on a GaAs layer. In this semiconductor light emitting device, after the semiconductor layers are grown on the substrate, an alternate supporting member composed of a flexible and conductive film is attached to the semiconductor layer. The substrate is then removed by etching, and a metallic electrode is formed on a surface of the InGaAlP layer from which the substrate is removed to manufacture the semiconductor device.
As described above, in the semiconductor light emitting device of Patent Literature 1, the removal of the substrate reduces the absorption of light emitted from the light emitting layer, thus increasing the output light emitted to the outside.
However, the semiconductor light emitting device of Patent Literature 1 has a difficulty in forming an ohmic contact between the metallic electrode and semiconductor layers because the GaAs substrate is removed and the metallic electrode is formed on the InGaAlP layer exposed by the removal of the GaAs substrate.